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Quantitative vs Qualitative Research - Resources
Qualitative Research in Health Care, 4th ed by Provides the essential information that health care researchers and health professionals need to understand the basics of qualitative research Now in its fourth edition, this concise, accessible, and authoritative introduction to conducting and interpreting qualitative research in the health care field has been fully revised and updated. Continuing to introduce the core qualitative methods for data collection and analysis, this new edition also features chapters covering newer methods which are becoming more widely used in the health research field; examining the role of theory, the analysis of virtual and digital data, and advances in participatory approaches to research. Qualitative Research in Health Care, 4th Edition looks at the interface between qualitative and quantitative research in primary mixed method studies, case study research, and secondary analysis and evidence synthesis. The book further offers chapters covering: different research designs, ethical issues in qualitative research; interview, focus group and observational methods; and documentary and conversation analysis. A succinct, and practical guide quickly conveying the essentials of qualitative research Updated with chapters on new and increasingly used methods of data collection including digital and web research Features new examples and up-to-date references and further reading. The fourth edition of Qualitative Research in Health Care is relevant to health care professionals, researchers and students in health and related disciplines.
ARTICLE: Tips for learners of evidence-based medicine: 1. Relative risk reduction, absolute risk reduction and number needed to treat
The tips in this article are adapted from approaches developed by educators with experience in teaching evidence-based medicine skills to clinicians. Objectives include: Understanding risk and risk reduction, balancing benefits and adverse effects in individual patients, and calculating and using number needed to treat.
Absolute Risk Reduction (ARR)
The difference in the rate of outcomes between the control group of a study and the intervention group. For example, if 30% of people experience a serious event in the control group and 20% in the intervention group, the ARR is 10% (30%-20%).
Relative Risk Ratio (RRR)
A measure expressed by the risk of an event in the group receiving the intervention divided by the risk in the control group. A value of one implies no effect of treatment; less than one that the intervention reduced the risk of an event; and greater than one that the occurrence of the event is increased.This measure of risk is often expressed as a percentage increase or decrease, for example ‘a 20% increase in risk’ of treatment A compared to treatment B. If the relative risk is 300%, it may also be expressed as ‘a three-fold increase’.
Number Needed to Treat (NNT)
A statistical measure of the number of people who need to be given an intervention in order to observe a beneficial effect for one extra person. It is calculated from the risk difference. It is the inverse of the absolute risk difference.
PROMIS® : Patient-Reported Outcomes Measurement Information System
PROMIS is a set of person-centered measures that evaluates and monitors physical, mental, and social health in adults and children. It can be used with the general population and with individuals living with chronic conditions. Available in Spanish and many other languages, PROMIS measures are available for FREE and can be administered in multiple ways.
NIH Toolbox® is a multi-dimensional set of brief measures to assess cognitive, sensory, motor and emotional function that can be administered in two hours or less across diverse study designs and settings.
Critical Appraisal Worksheets
Appraisal resources on a variety of study types: